LONDON—Canary Wharf Group has agreed to sell 50 Bank Street, an office building in Docklands, East London, to the managing family of a Hong Kong conglomerate for £153.5 million pounds ($248.9 million).

The deal underscores confidence among overseas investors in London's commercial property sector as a haven. Foreign buyers accounted for 69% of the £4 billion poured into central London offices in the second quarter, according to real estate services company CBRE Inc.

Songbird Estates
PLC, Canary Wharf's parent, said on Wednesday that it sold the 216,000 square-foot building to Crosby Investment Holdings Inc.

Crosby is owned by
Vivien Chen,
the head of Nan Fung Group, a business dynasty with holdings in textiles, real estate and shipping.

In other recent deals,
China Life Insurance Co
mpany Ltd., a state-backed insurer, took a 70% stake in 10 Upper Bank Street, one of Docklands' largest skyscrapers with over a million square feet of office space, when Canary Wharf sold it for £795 million in June. Qatar's sovereign-wealth fund Qatar Holding LLC, a Songbird shareholder, bought 20%.

Canary Wharf Group said the proceeds of the sale will be invested in its new developments.

Canary Wharf has aspirations to become one of London's biggest residential developers even though the Docklands estate—the London home of Barclays PLC, Citigroup Inc and Credit Suisse Groupe AG—was conceived as a rival financial center to the City of London.

In March the company won planning consent to develop its Newfoundland site—a 58-story apartment building east of Docklands—while its Wood Wharf development, which will include 3,100 apartments, was approved in July.

Canary Whaft is redeveloping Royal Dutch Shell PLC's former London headquarters, slated to see 877 more homes built on central London's South Bank.